An organic-inorganic hybrid K 2 TiF 6  : Mn 4+ red-emitting phosphor with remarkable improvement of emission and luminescent thermal stability.

A new type of monoethanolamine (MEA) and Mn 4+ co-doped KTF : MEAH + , Mn 4+ (K 2 TiF 6  : 0.1MEAH + , 0.06Mn 4+ ) red emitting phosphor was synthesized by an ion exchange method. The prepared Mn 4+ co-doped organic-inorganic hybrid red phosphor exhibits sharp red emission at 632 nm and the emission intensity at room temperature is 1.43 times that of a non-hybrid control sample KTF : Mn 4+ (K 2 TiF 6  : 0.06Mn 4+ ). It exhibits good luminescent thermal stability at high temperatures, and the maximum integrated PL intensity at 150 °C is 2.34 times that of the initial value at 30 °C. By coating a mixture of KTF : MEAH + , Mn 4+ , a yellow phosphor (YAG : Ce 3+ ) and epoxy resin on a blue InGaN chip, a prototype WLED (white light-emitting diode) with CCT = 3740 K and R a = 90.7 is assembled. The good performance of the WLED shows that KTF : MEAH + , Mn 4+ can provide a new choice for the synthesis of new Mn 4+ doped fluoride phosphors.